On Iran, can U.S. policymakers take ‘yes’ for an answer?

Iran’s new president is striking a moderate tone, and Tehran appears more open to engagement and a deal with Washington than at anytime in a decade. What remains to be seen is whether the Iranian tone will be matched by a willingness to accept some constraints on its nuclear program, and whether the United States will lift sanctions on Iran in return.

For 30 years, Iranian and American leaders have eyed each other with distrust. Now leaders of both countries appear to see a gleam of hope that the two former allies can overcome their recent history of grievance and violence to head off a confrontation that neither country wants.

President Obama has been ready for engagement with Iran since he entered office. He ran on a platform that included being willing to engage with adversaries including North Korea and Iran, but early efforts to pursue diplomatic engagement proved fruitless. Even as he wound down the wars in Iraq and Afghanistan, and sought to avoid entanglement in Syria, one eye was always on how to manage the Iran dilemma.

Iranian leaders have been swimming in a sea of even stronger currents. After suppressing the green movement in 2009 and witnessing the great upheavals of the Arab Spring, Iran’s Supreme Leader Ayatollah Khamanei permitted the election of President Hassan Rouhani. Rouhani appears to have been acceptable to the Surpreme Leader because he doesn’t try to undermine the basic premise of the Iranian revolution, ensuring that religious leaders will retain a key voice in government affairs.

Since taking office, President Rouhani has said he has full authority to negotiate over the nuclear issue and has made some promising moves for those who hope for a more moderate Iran. He appointed the western educated ambassador Javad Zarif as his foreign minister, released some political prisoners, reopened a closed movie house in Tehran, and lifted some internet restrictions for the Iranian people. He even has his own Twitter account, which he used earlier this month to convey Rosh Hashanah greetings to Jews in Iran and around the world.

None of this proves that Iran will be willing or able to resolve the outstanding concerns over its nuclear intentions. Promises–including statements by Khamenei that the development of nuclear weapons is forbidden by the teachings of Islam–have proven insufficient to allay American concerns. Given the number of facilities Iran is building that could produce weapons-grade materials, the White House is waiting to see if the new president is willing to accept concrete constraints on Iran’s nuclear program. Such steps include verifiably stopping all enrichment above 5% or accepting a verified cap on the amount of enriched uranium Iran would possess at any time.

These steps would permit the peaceful use of nuclear technology, but create major barriers to producing a nuclear weapon. Another possible constraint could include limiting the number of operating uranium enrichment centrifuges at the Natanz or Fordow facilities. Full compliance with inspection requirements would be essential.

Of course, some Americans (and Israelis) are skeptical of Rouhani. His moderate tone may not lead to changed policies by the government as a whole, and in many ways it was easier to rally support for sanctions in the face of the often offensive remarks from former President Ahmadinejad. Where policymakers used to take comfort in the fact that the former president had no real authority in Iran, they may soon lament that the new president is equally powerless to shape policy.

Of course, America has its own policy challenges as it considers the potential benefits of renewed engagement. Tehran’s objective is to end the sanctions on Iran’s oil based economy. President Obama has the authority to lift many of these economic penalties. An obstructionist Congress, however, may seek to impose or toughen other sanctions to thwart any deal with Iran, just as lawmakers did to President Clinton with North Korea in the 1990s.

Iran’s support for terrorist groups, its tough statements against Israeli policies, and other actions that are at odds with American security interests will remain problems even if a solution to the nuclear standoff can be found. In short, the real question is whether American policy makers, including in Congress, can accept yes for an answer to the nuclear question–even if other disagreements remain.